The present invention relates to logic devices for use in computers and other computational devices utilizing light beams, and more particularly to a light actuated switching device which functions as an optical AND gate, INVERTER, or BUFFER.
Communication and computational systems utilizing switched light beams have the potential of providing substantial improvements in telephone and computer systems. Fiber optic transmission lines are already being utilized to increase the capacity of telephone systems. Computing devices based on switching light beams hold the promise of dramatic increases in the capacity and speed of computers.
Computational devices based on circuits in which light signals serve a function analogous to that served by electrical signals in conventional computers have long been sought as a means of dramatically increasing the computational capacity of computers. Such devices would utilize optical fibers to transmit signals between various logic elements. Ideally, the logic elements would operate directly on these light signals to produce other light signals representing the results of the computations. In practice, most light switching circuits rely on electrical signals for their control. As a result, the logic elements based on these circuits are limited in speed.
For example, optical equivalents to a logical AND gate are typically generated by first converting the two light signals to electrical signals which are then processed by a conventional AND gate. The output signal generated by the electrical AND gate is then converted to a light signal by a laser diode. The speed of the AND gate is hence limited by the speed with which the electrical components can operate.
Broadly, it is an object of the present invention to provide an improved optical AND gate switching device which generates a light output signal in response to the simultaneous presence of two specified light input signals.
It is a further object of the present invention to provide an optical AND gate switching device which is not limited by the speed at which electrical signals can be switched.
These and other objects of the present invention will become apparent to those skilled in the art from the following detailed description of the invention and the accompanying drawings.